Peganum harmala is a perennial shrub with fleshy spikey-looking leaves, growing up to 1 meter tall. Its small, brown seeds contains harmine and other harmala alkaloids. It is one of the plants speculated to be the Soma or Haoma of ancient Persia.

Syrian Rue grows in semi-arid conditions. It originated in Central Asia, and is held in high esteem throughout Asia Minor as an dye plant. It is sometimes known as 'ruin weed' since it often grows on the tells covering the ruins of ancient cities in the Near East. It now grows wild in Eurasia and has recently been spread to Texas, Nevada, New Mexico and Southern California.

A red dye, "Turkey Red," from the seeds is often used in Western Asia to dye carpets. It is also used to dye wool. When the seeds are extracted with water, a yellow fluorescent dye is obtained. If they are extracted with alcohol, a red dye is obtained. The stems, roots and seeds can be used to make inks, stains and tattoos.